Husqvarna 350...muffler heat shield?

[Dadsaws]

I picked up a used Husqvarna 350 recently. Ad said that it needs a muffler but comes with a new one... and it runs. The tank was bone dry when I got it. I added gas and it fired after 10 pulls or so. This is all without a muffler installed. The plastic body below muffler looks quite toasty. I'll include pics of the toasty area. I'm looking for an ipl of a 350 but can't find info that I'm looking for. Does a 350 have a heat shield or deflector that goes behind muffler and maybe also protect plastic above bar oil reservoir?

 

[grizz55chev]

I picked up a used Husqvarna 350 recently. Ad said that it needs a muffler but comes with a new one... and it runs. The tank was bone dry when I got it. I added gas and it fired after 10 pulls or so. This is all without a muffler installed. The plastic body below muffler looks quite toasty. I'll include pics of the toasty area. I'm looking for an ipl of a 350 but can't find info that I'm looking for. Does a 350 have a heat shield or deflector that goes behind muffler and maybe also protect plastic above bar oil reservoir?

There is a shield between the muffler and the cylinder, but not the plastic oil reservoir, only a foil decal(?). The reason for the burned area is most likely stripped muffler bolts, and a lose muffler. Check the threads on the cylinder.

 

[Woodslasher]

There is a shield between the muffler and the cylinder, but not the plastic oil reservoir, only a foil decal(?). The reason for the burned area is most likely stripped muffler bolts, and a lose muffler. Check the threads on the cylinder.

The 350 I got had two shields, the aluminum behind the muff type and a steel one that wrapped down underneath the muffler to protect the case from this exact type of damage. I'm pretty sure a look in later husky 350 ipl's would show it and a p/n, I just don't have the time to find it now.

 

[grizz55chev]

The 350 I got had two shields, the aluminum behind the muff type and a steel one that wrapped down underneath the muffler to protect the case from this exact type of damage. I'm pretty sure a look in later husky 350 ipl's would show it and a p/n, I just don't have the time to find it now.

I believe you are correct, it's a common occurrence for them to rattle lose and burn the case below the exhaust.

 

[user 74409]

The later 350's with 52cc cylinders (45mm bore) were more prone to harmonic vibration at higher rpm resulting in muffler bolts backing out. A cheap fix for stripped threads is tap cylinder to 1/4:-20 and use 1/4"-20 x 3-1/2" socket head cap screws. Must run 1/4" drill bit through muffler holes to clearance for larger screws. One enhancement is to add 346xp muffler support (cut flywheel side leg off) to help stabilize muffler to prevent future problems.

 

[user 74409]

See listing below for part number and photo of steel heat shield

https://www.ebay.com/itm/1659077991...DYh8Cx3LShIh7ICVPBQLsDDVO7|tkp:Bk9SR4z2hoLLYQ

 

[david newbie]

I think there is a way to use a 353. or 346 muffler bracket, maybe the muffler is less likely to vibrate loose with that?

 

[Dadsaws]

See listing below for part number and photo of steel heat shield

https://www.ebay.com/itm/1659077991...DYh8Cx3LShIh7ICVPBQLsDDVO7|tkp:Bk9SR4z2hoLLYQ

So the shield in that link is for the 52cc version? That is what I have.

 

[Dadsaws]

I think there is a way to use a 353. or 346 muffler bracket, maybe the muffler is less likely to vibrate loose with that?

I was hoping to convert this to a 346xp anyway. I'll look into that. I'm surprised there isn't a loctite product that doesn't work for muffler bolts

 

[user 74409]

This fits the 52cc engine. Use both aluminum and steel shields. Vibration from loose muffler bolts commonly damage threads. Red or blue Loctite are used successfully in many cases.

The 50cc 346xp engine with fit with modifications. There is interference between engine and case on clutch side. Trim back plastic reinforcing ribs as needed. The screws holding cylinder down can be slightly too long by about .050". Either grind screws slightly as needed or buy 346xp screws, if cylinder cannot be tightened down firmly with 52cc bolts. Install flywheel and verify flywheel does not rub on cylinder.

 

[Woodslasher]

This fits the 52cc engine. Use both aluminum and steel shields. Vibration from loose muffler bolts commonly damage threads. Red or blue Loctite are used successfully in many cases.

The 50cc 346xp engine with fit with modifications. There is interference between engine and case on clutch side. Trim back plastic reinforcing ribs as needed. The screws holding cylinder down can be slightly too long by about .050". Either grind screws slightly as needed or buy 346xp screws, if cylinder cannot be tightened down firmly with 52cc bolts. Install flywheel and verify flywheel does not rub on cylinder.

I think it should fit all those saws, it fit an oem 350 top end and a 346 ne top end with no mods, I'd think it would be plug and play for the rest too.

 

[Wood Doctor]

I think there is a way to use a 353. or 346 muffler bracket, maybe the muffler is less likely to vibrate loose with that?

Yes there is a way. Here's my solution:

I reshaped the part for the 353. It holds tight and so do the bolts.